The present invention relates generally to inlet air treatment systems, and more specifically to systems and methods for bypassing inlet air pre-filter systems for gas turbine engines.
At least some gas turbine engines include a compressor section, a combustor section, and at least one turbine section. The compressor compresses air, which is mixed with fuel and channeled to the combustor. The compressor compresses air, that is mixed with fuel and channeled to the combustor. The mixture is then ignited generating hot combustion gases that are then channeled to the turbine. The turbine extracts energy from the combustion gases for powering the compressor, as well as producing useful work to power a load, such as an electrical generator, or to propel an aircraft in flight.
At least some known gas turbine engine systems include inlet air treatment systems that remove moisture and/or dust from air channeled to the compressor. At least some known inlet air filtration systems include pre-filters that remove moisture from intake air, and final filters that remove dust and debris from intake air. During normal operating conditions, it is desired to have the inlet air treatment system channel filtered air to the compressor with minimal air disruption and pressure drop through the inlet air treatment system. However, at least some known pre-filters cause a pressure drop of about 0.5″ of water column under normal operating conditions. Over time, the pressure drop across the pre-filters and filter may increase which may result in reducing an amount of air flow to the compressor and reducing the operating efficiency of the gas turbine engine. In some instances, the reduced air flow may cause a compressor surge that may damage the compressor. To prevent compressor surges, in at least some known inlet air treatment systems, pre-filters have to be removed manually to be cleaned. This removal process may require shutdown of the gas turbine engine for a period of 3 to 4 days.
Accordingly, it is desirable to provide a method and/or system for bypassing the pre-filter during periods when the pressure drop through the inlet air treatment system is high enough to reduce compressor operating efficiency and/or to result in a reduced air flow that may cause a compressor surge. Moreover, it is desirable to provide a system that does not require the pre-filters be manually removed from service during operation of the turbine engine.